This is a rare early 1800's wooden dovetailed purpose made developing box. It is meant to hold the tintypes while the solution added helps the picture to stay on tin or copper plate. It measures 13" long by 7 3/4" wide. It is 5 1/2" tall and features a double thumb press unlocking. The inside features the original metal closing piece and three black double holed pieces that hold the solution. This is a collector piece hard to come by.